Synchronous motor



April 18, 1939. w, L, HANSEN AL I 2355,266

SYNCHRONOUS MOTOR Original Filed May 5. 1956 Patented Apr. 18, 1939PATENT OFFICE SYNCHRONOUS MOTOR William L. Hansen and Ira N. Hurst,Princeton, Ind., assignors to Hansen Mfg. Company, Inc., Princeton,Ind.,- a corporation of Indiana Original application Mays; 1936, SerialNo. 78,002. Dividedand this application April 12,

1937, Serial No. 136,503

2 Claims. .(01. 172-120) Our invention relates to synchronous motorsand, in particular, to rotors for such motors.

One object of our invention is to provide a rotor of continuous diskform which has a plurallty of synchronized poles in the disk such asfoursynchronizing poles, and by this construction assuring aself-starting motor.

It is a further object to provide a rotor having the samecharacteristics in which the poles are formed by punched sections havingtongues punched from the metal and bent back until the ends of thetongues just reach the outer rim of the disk.

This application is a division of our applica tion filed May 5, 1936,Serial No. 78,002. Y I Referringto the drawing, Figure 1 is a frontelevation of the motor.

Figure 2 is a side elevation thereof showing the motor and gear box.

8. Figure 10 is a front elevation of another form of rotor.

Figure 11 is a section on the line l| -Il Figure 10.

Referring to the drawing in detail, the laminations comprising themagnet field plates of the motor are designated generally I. Theselaminations consist of an arcuate portion 2, a relatively small unshadedpole 3 and a relatively large shaded pole I. One-half of the laminationson .one side have the small pole' at the top and the large pole at thebottom. The other half of the laminations on the other side have thelarge pole at the top and the small pole atthe bottom.

At the bottom of the laminations are laterally projecting portions 5extending to and overlapping upon the depending portion 6 of the adiacent laminations. These members 5 bridge the gap l between the two setsof laminations, in

which gap is mounted the field coil 8, which is connected to a source ofelectrical energy through the wires 9 and III in the usual manner.

the sleeves l5 oi the gear box casing I 6.

The large poles! are about two-thirds larger than the smaller poles 3.Thus we are enabled to balance the power in the shaded pole to that ofthe unshaded pole. The poles l have mounted on them the shading coils orplates Ii.

It will be noted that the interior faces of the poles are arcuate so asto be brought in close parallel relationship with the periphery of therotor generally designated i2, the exact construction of which will behereinafter explained.

The laminations l are bolted together by the bolts i3 through thedepending portions 6 and the laterally extending portions 5. They arealso bolted together by the bolts H which project into The gear box I6is a casing provided with supporting ears I I. The details of this gearbox are not important.

Referring to the rotor of Figures 6 and 7, the rotor I2 is mounted on ashaft it which extends into the gear box I6 for driving the gearstherein. i9 is a pinion on the outside of the gear box driven by thegears in the gear box so actuated by the shaft i8.

The rotor consists of the pair of spaced plates 20 and 2| that areidentical with oneanother. These plates have struck-up ribs 22 arrangedopposite to one another so that there are enlarged spaces 23 atpredetermined intervals between the plates. Thus this rotor of thinheat-treated carbon steel is so drawn as to bring more metal into therib areas 22 to form four synchronizing poles 9, in which one or moredisks 24 are pressed from annealed carbonsteel so that the spokesections constituting the four poles 25 and the rim 26 are left fullthickness, while the intermediate areas 21 are thinner. Thisconstruction also gives a self-starting rotor and a self-starting motor.The rotor of Figures 8 and 9, after being so pressed with theidentations 21, is hardened.

Referring to Figures 10 and 11, apair of metal disks are punched withfour'openings 28. The tongue material so punched to form the openings isturned backwardly and outwardly as at 29 so that an additional mass ofmaterial is provided where the tongues engage one another face to facebetween the respective disks of metal 30. The ends of the tongues justreach the outer rims of the disks.

It will beunderstood that we desire to comprehend within our inventionsuch modifications as may be necessary to adapt it to varyingconditionsand uses.

iii?

he un stood that with the four-pole rotor this twi synchronous "oi-poleconstruction the speed is 1800 R. P. M. It the rotor is divided into sixpoles the speed will be 1200 P. P. M. By arranging the rotor in variousdivisions, various speeds may be secured.

Having thus fully described our invention, what we claim as new anddesire to secure by Letters Patent, is: 7

1. A rotor for a self-starting synchronous motor comprising a metal diskwith perforations dis posed intermediate the center and peripherythereof, the material from the perforations being turned over at theouter edge 01' each per- Ioration and directed outwardly parallel to theface of the disk whereby pole areas are formed in the disk periphery ofa greater amount of metal than in the central areas thereof,

2. A rotor unit for a self-starting synchronous motor comprising a pairof spaced metal disks having tongues punched therefrom and turnedbackwardly and outwardly toward the peripheries thereof, the tongues ofone disk being bent into adjacent parallel relationship with the

